Protection device

ABSTRACT

A protection device for a pregnant person in a vehicle is described, a sensor being provided for detecting the pregnant person and a restraint unit being configured in such a way that the usability of the restraint unit is influenceable as a function of a signal of the sensor. The restraint unit may be disabled in the event of an accident or its deployment force may be reduced or it is usable depending on the situation.

FIELD OF THE INVENTION

The present invention is directed to a protection device for a pregnantperson in a vehicle.

SUMMARY OF THE INVENTION

The protection device according to the present invention for a pregnantwoman in a vehicle has the advantage that the restraint means in avehicle for the pregnant woman are activated in the event of an accidentin such a way that the risk of injury to the woman and the unborn childare minimized.

It is particularly advantageous that first restraint means are disabledin the event of an accident if the presence of a pregnant woman isdetected in order to minimize the risk of injury to the unborn child inparticular, and the deployment force of second restraint means isreduced so that soft airbags are used, and third restraint means areprovided which may be used depending on the situation. This includesrestraint means offering optimum protection to the pregnant woman inparticular in the event of an accident and as a function of the type ofaccident and her physical situation.

Furthermore, it is advantageous that the first restraint means aredesigned in such a way that seat belt locking and seat belt tensioningare disabled in the event of a frontal and/or side and/or rear impact.In the event of a frontal, rear, and side crash, the force of the lapbelt and sometimes even of the shoulder belt, as well as of the steeringwheel rim acting on the mother's abdomen, may cause injury or death tothe unborn child. It is furthermore advantageous that the firstrestraint means disable seat belt locking in the event of rollover andtension the lap belt using a power belt tensioner when a predefined rollangle is reached. This roll angle is preferably 50°. This prevents theeffect of force on the unborn child and at the same time secures thepregnant woman.

The second restraint means are advantageously configured in such a waythat they are usable early using a low deployment force as a softairbag, as opposed to its use for a non-pregnant person. Such softairbags may also be used on the backrests of the front seats forpregnant persons sitting in the rear. Further protection may be achievedvia “inflatable carpets” for expectant mothers sitting in the frontseat.

It is furthermore advantageous that the third restraint means have aknee bag for preventing the pregnant person from slipping through theseat belt and/or a device for retracting the steering wheel and/or anairbag for cushioning the steering wheel.

It is furthermore advantageous that a display is configured in such away that the detection of a pregnant person is displayable. This permitschecking of the protection device according to the present invention inparticular.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention are illustrated in thedrawing and explained in greater detail in the description that follows.

FIG. 1 shows a block diagram of the device according to the presentinvention.

FIG. 2 shows an exemplary embodiment of the disabling device for theseat belt locking output stages.

DETAILED DESCRIPTION OF THE INVENTION

Research has found that the most common cause of death of unbornchildren in the U.S. is automobile accidents. Not only is the risk of acrash the same for the fetus as for the pregnant mother, but the risk ofinjury is much higher, so that according to the present invention aprotection device is provided, which is to offer the unborn child inparticular optimum protection in the event of an accident.

The first prerequisite for protecting the unborn child is a sensor forrecognizing women in an advanced stage of pregnancy. Such a sensor maymeasure the breathing and heart frequencies, for example. Because onlyone breathing pattern but two heartbeats are to be measured for anexpectant mother, a pregnant woman may thus be recognized. A vibrationsensor, for example, a piezoelectric vibration sensor, is preferablyused for this purpose.

In the event of a frontal, rear, and side crash, the unborn child maysuffer injuries or death due to the force exerted by the lap belt andsometimes also by the shoulder belt, as well as by the steering wheelrim on the mother's abdomen.

If a pregnant woman is detected according to the present invention, noseat belt locking and no seat belt tensioning is to take place in theevent of a frontal, rear or side crash. The submarining effect, i.e.,slipping through the seat belt, must be prevented by the deployment ofthe knee bag and the early deployment of a less aggressive, i.e., soft,airbag, including on the backrests of the front seats for pregnant womensitting in the rear. Extended protection may be provided by “inflatablecarpets” for expectant mothers sitting in the front seat.

For the pregnant woman driving the vehicle, the steering wheel mustadditionally be retracted toward the front, preferably by apyrotechnical actuator to obtain more clearance between the mother andthe hard steering wheel parts. A suitably shaped airbag may also softlycushion the surface of the steering wheel including the steering wheelrim.

In the event of a rollover, seat belt locking should also be disabled;however, the lap belt should preferably be tensioned using a power belttensioner after the vehicle has reached the stability roll angle ofapproximately 50° and the pregnant woman has been somewhat lifted offthe seat. Impact of the pregnant woman's head against the roof must beavoided in the event of a rollover. The lap belt then presses againstthe woman's thighs, rather than her abdomen.

Seat belts are nowadays mostly locked using a mechanical sensor in thebelt retractor, which acts directly upon the locking mechanism. Suchsensors are no longer to be used for protecting the unborn child.

There are also electronic inclination and position sensors in which theprinciple of measurement is the change in the magnetic flux [measuredusing] a magnetic Hall system or with an optical system. Such a sensorcould be used centrally in the vehicle for electrical triggering of allseat belt locking devices. If the presence of a pregnant woman isdetected, the corresponding seat belt is not locked.

The airbag is deployed and the deployment of the seat belt tensioner isprevented in the event of a longitudinal or transverse impact, and thelap belt tensioner is triggered in the event of rollovers using theexisting airbag deployment device using the triggering thresholdsadjusted to the requirements of optimum protection for pregnant women.These thresholds are also modified as a function of time. The same holdstrue for activation of the steering wheel retractor.

FIG. 1 shows as a block diagram the protection device according to thepresent invention. A sensor 1 for detection of the pregnant woman isconnected to a processor 2 in the airbag control unit. Sensor 1 isconnected here to processor 2 via a two-wire line, i.e., data is onlytransmitted from sensor 1 to processor 2. As an alternative, a busconnection may also be provided between sensor 1 and processor 2. Asimple bidirectional transmission link may also be provided here. Sensor1 is a vibration sensor which works by the piezoelectric principle. Itis therefore capable of detecting the pulse frequency and the breathingfrequency of individuals in the passenger compartment. Sensor 1 ispositioned so that it only registers the pulse frequency and breathingfrequency of the individual sitting in a particular seat. If a pregnantperson is sitting in the seat, the sensor detects only one breathingfrequency, but at least two pulse rates. The pulse rate of the child ishigher than that of the mother. A pregnant person may thus be detected.

Processor 2 is connected to first restraint means 4 via a first dataoutput. These are restraint means whose function may be disabled as afunction of the signal from sensor 1. They include belt tensioners andairbags. Processor 2 is connected to second restraint means 5, whosedeployment force may be reduced as a function of the signal from sensor1, via a second data output. Such restraint means include airbags inparticular which are then triggered early, but with less intensity inthe event of an accident. “Early” means here that the airbag is deployedearlier than in the case of a normal person to be protected. A “normalperson” is understood here to be a non-pregnant person. “Soft airbag”means that the rate at which the airbag is inflated and the rate andmass flow of gas introduced into the airbag are reduced. This minimizesthe risk of injury by the airbag. Processor 2 is connected to thirdrestraint means 6, which are used in particular for protecting apregnant person, via a third data output. Restraint means 6 may be aknee bag which is to prevent the person from slipping through the seatbelt. Furthermore, restraint means 6 are to be understood as a devicefor retracting the steering wheel. This device, which operates by apyrotechnical principle, is used in the event of an accident when thepregnant person is the driver of the vehicle. Injuries by impact of thepregnant woman against the steering wheel are thus minimized. Inaddition, restraint means 6 are to be understood as an airbag for thesteering wheel rim which is deployed in the event of an accident. Thisminimizes injuries when the pregnant person contacts the steering wheelrim.

Furthermore, processor 2 is connected to a display 7, which shows that apregnant person has been detected in a particular seat. As analternative, the display may only show that a pregnant person has beendetected in general. Processor 2 in the airbag control unit isfurthermore connected to a sensor system 3 via a second data input, fromwhich processor 2 receives the information that an accident is imminent,for example, from a pre-crash sensor system, and/or that an impact hasoccurred. For this purpose, impact sensors designed as accelerationsensors, for example, are used. Such impact sensors may be situated inthe airbag control unit, which is preferably situated centrally in thevehicle, or outside this control unit. Such sensors may then beperipheral sensors which are distributed in the vehicle. Such sensorsmay be used in the front of the vehicle as upfront sensors. Instead ofacceleration sensors, pressure sensors, temperature sensors, or otherdeformation sensors may be situated in the sides of the vehicle assatellite sensors.

FIG. 2 shows in an exemplary block diagram how seat belt locking may bedisabled as a function of the signal from a sensor for the pregnantwoman. A sensor 8 for detecting a pregnant woman is connected to anegation element 11. Negation element 11 is connected to an AND gate 13.A seat belt locking sensor 9, which shows that the seat belts are to belocked to restrain a person to be protected using a restraining force,is connected to a second input of AND gate 13. The negated signal ofpregnancy sensor 8 is relayed to the airbag and seat belt tensionerdeployment logic to initiate, also in this case, appropriate measures asexplained above, for example, to deploy a soft airbag, deploy additionalknee bags, or to tighten the lap belt using a power belt tensioner inthe event of a rollover.

If a pregnant person is detected by sensor 8, AND gate 13 issues a logic0 in the event of an accident when locking sensor 9 issues a logic 1.Seat belt locking output stage 15 for the seat where the pregnant personwas detected is thus not activated, since seat belt locking output stage15 is connected to the output of AND gate 13. Seat belt locking outputstage 15 is also connected to seat belt locking device 17 for this seat.Seat belt locking output stage 15 is only activated when AND gate 13issues a logic 1. However, the AND gate issues a logic 1 only whensensor 8 generates a logic 0 and seat belt locking sensor 9 issues alogic 1, i.e., when an accident is detected.

Seat belt locking sensor 9 is furthermore connected to an AND gate 14,which is assigned to another seat. A sensor 10 for detecting a pregnantperson, which is connected to a negation gate 12, is also provided forthis seat. Negation gate 12 is connected to the second data input of ANDgate 14. The output of negation gate 12 is furthermore connected to theairbag and seat belt tensioner deployment logic to activate the secondand third restraint means as needed. The output of AND gate 14 isconnected to seat belt locking output stage 16, which is in turnconnected to the seat belt locking device for seat 18. It is thus clearthat seat belt locking sensor 9 is connected to all seat belt lockingoutput stages for the particular seats. However, dedicated sensors 8 and10 are provided for each seat for detecting a pregnant person.

1. A protection device for a pregnant person in a vehicle, comprising: asensor (1, 8, 10) which detects whether a person in the vehicle ispregnant, and restraint means (4 through 6) which is activatable in sucha way that usability of restraint means (4 through 6) is influenceableas a function of a signal of the sensor (1, 8, 10).
 2. The protectiondevice according to claim 1, wherein the protection device includesfirst restraint means (4) which may be disabled in the event of anaccident, second restraint means (5) whose deployment force isreducible, and third restraint means (6) which is usable depending onthe situation.
 3. The protection device according to claim 2, whereinthe first restraint means (4) is designed in such a way that it disablesa seat belt locking and a seat belt tensioning in the event of a frontalor side or rear impact.
 4. The protection device according to claim 3,wherein a display (7) is configured in such a way that the detection ofthe pregnant person is displayable.
 5. The protection device accordingto claim 2, wherein the second restraint means (5) is configured in sucha way that the second restraint means (5) is usable early using areduced deployment force compared to the case of a non-pregnant person.6. The protection device according to claim 5, wherein a display (7) isconfigured in such a way that the detection of the pregnant person isdisplayable.
 7. The protection device according to claim 2, wherein thethird restraint means (6) has a knee bag for preventing the person fromslipping through the seat belt or a device for retracting the steeringwheel or an airbag for cushioning the steering wheel.
 8. The protectiondevice according to claim 7, wherein a display (7) is configured in sucha way that the detection of the pregnant person is displayable.
 9. Theprotection device according to claim 2, wherein a display (7) isconfigured in such a way that the detection of the pregnant person isdisplayable.
 10. The protection device according to claim 1, wherein adisplay (7) is configured in such a way that the detection of thepregnant person is displayable.
 11. A protection device for a pregnantperson in a vehicle, comprising: a sensor (1, 8, 10) for detecting thepregnant person and restraint means (4 through 6) which is activatablein such a way usability of restraint means (4 through 6) isinfluenceablenas as a function of the sensor (1, 8, 10); wherein theprotection device includes first restraint means (4) which may bedisabled in the event of an accident, second restraint means (5) whosedeployment force is reducible, and third restraint means (6) which isusable depending on the situation; and wherein the first restraint means(4) disables seat belt locking in the event of a rollover and tensions alap belt using a power belt tensioner when a predefined roll angle isreached.
 12. The protection device according to claim 11, wherein thepredefined roll angle is approximately 50°.
 13. The protection deviceaccording to claim 12, wherein a display (7) is configured in such a waythat the detection of the pregnant person is displayable.
 14. Theprotection device according to claim 11, wherein a display (7) isconfigured in such a way that the detection of the pregnant person isdisplayable.